Edited to show only the threads indicated by the issue description.

This backtrace is typical of the DEBUG_THREADS caused deadlock because a
thread is stuck waiting for the ast_reentrancy_lock.


Thread 49 (Thread 0x7fbbb64ac700 (LWP 16623)):
#0  0x0000003b4820e264 in __lll_lock_wait () from /lib64/libpthread.so.0
#1  0x0000003b48209523 in _L_lock_892 () from /lib64/libpthread.so.0
#2  0x0000003b48209407 in pthread_mutex_lock () from /lib64/libpthread.so.0
#3  0x00000000004e7914 in ast_reentrancy_lock (lt=0x7fbbe8001990) at /home/admin_tg/rpmbuild/BUILD/asterisk-1.8.28.cert1/include/asterisk/lock.h:420
#4  0x00000000004e8255 in __ast_pthread_mutex_lock (filename=0x642eb4 "devicestate.c", lineno=502, func=0x643610 "ast_devstate_changed_literal", mutex_name=0x64314f "&(&state_changes)->lock", t=0x8d4b90) at lock.c:218
#5  0x00000000004a243e in ast_devstate_changed_literal (state=AST_DEVICE_UNKNOWN, cachable=AST_DEVSTATE_CACHABLE, device=0x7fbbb64a52c0 "SIP/besier_02") at devicestate.c:502
#6  0x00000000004a25ca in ast_devstate_changed (state=AST_DEVICE_UNKNOWN, cachable=AST_DEVSTATE_CACHABLE, fmt=0x7fbc03dc9543 "SIP/%s") at devicestate.c:525
#7  0x00007fbc03d3562c in update_call_counter (fup=0x7fbadc011238, event=0) at chan_sip.c:6349
#8  0x00007fbc03d361b7 in sip_hangup (ast=0x7fbadc04dde8) at chan_sip.c:6610
#9  0x0000000000470276 in ast_hangup (chan=0x7fbadc04dde8) at channel.c:2887
#10 0x00007fbc08117972 in dial_exec_full (chan=0x7fbba53828c8, data=0x7fbbb64a9430 "SIP/+xxxxxxxxx1167@besier_02,120,g", peerflags=0x7fbbb64a7200, continue_exec=0x0) at app_dial.c:3065
#11 0x00007fbc08117d35 in dial_exec (chan=0x7fbba53828c8, data=0x7fbbb64a9430 "SIP/+xxxxxxxxx1167@besier_02,120,g") at app_dial.c:3119
#12 0x000000000050d7f8 in pbx_exec (c=0x7fbba53828c8, app=0x10c9a400, data=0x7fbbb64a9430 "SIP/+xxxxxxxxx1167@besier_02,120,g") at pbx.c:1502
#13 0x00000000005180e1 in pbx_extension_helper (c=0x7fbba53828c8, con=0x0, context=0x7fbba5382f10 "Kxxxxxxxx0_trunk_in_cntx", exten=0x7fbba5382f60 "xxxxxxxx1167", priority=30, label=0x0, callerid=0x7fbadc016f00 "+496131625349", action=E_SPAWN, found=0x7fbbb64abb58, combined_find_spawn=1) at pbx.c:4762
#14 0x000000000051aab9 in ast_spawn_extension (c=0x7fbba53828c8, context=0x7fbba5382f10 "Kxxxxxxxx0_trunk_in_cntx", exten=0x7fbba5382f60 "xxxxxxxx1167", priority=30, callerid=0x7fbadc016f00 "+496131625349", found=0x7fbbb64abb58, combined_find_spawn=1) at pbx.c:5660
#15 0x000000000051b55b in __ast_pbx_run (c=0x7fbba53828c8, args=0x0) at pbx.c:5763
#16 0x000000000051d2a3 in pbx_thread (data=0x7fbba53828c8) at pbx.c:6104
#17 0x0000000000576bbb in dummy_start (data=0x7fbba4a2a330) at utils.c:1151
#18 0x0000003b482079d1 in start_thread () from /lib64/libpthread.so.0
#19 0x0000003b47ae886d in clone () from /lib64/libc.so.6

Thread 7 (Thread 0x7fbc0a1aa700 (LWP 11301)):
#0  0x0000003b4820b5bc in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00000000004e9374 in __ast_cond_wait (filename=0x642eb4 "devicestate.c", lineno=549, func=0x6435f0 "do_devstate_changes", cond_name=0x643167 "&change_pending", mutex_name=0x643177 "&state_changes.lock", cond=0x8f0060, t=0x8d4b90) at lock.c:565
#2  0x00000000004a2717 in do_devstate_changes (data=0x0) at devicestate.c:549
#3  0x0000000000576bbb in dummy_start (data=0x2b20690) at utils.c:1151
#4  0x0000003b482079d1 in start_thread () from /lib64/libpthread.so.0
#5  0x0000003b47ae886d in clone () from /lib64/libc.so.6